Showerhead assembly and plasma processing apparatus

Abstract

To provide a shower head, an electrode unit, a gas supply unit, a substrate processing apparatus, and a substrate processing system that improve corrosion resistance against process gas.SOLUTION: In a shower head for plasma processing, a body portion BD has a first surface BD1, a second surface BD2 opposite to the first surface, and a plurality of inner surfaces BD3, and the inner surfaces define a plurality of gas holes penetrating the body portion from the first surface to the second surface. The second surface is made of a first corrosion-resistant material.SELECTED DRAWING: Figure 1B

Description

[Technical Field]

[0001] An exemplary embodiment of the present disclosure includes a showerhead, an electrode unit, a gas supply unit, a substrate, The present invention relates to a processing apparatus and a substrate processing system. [Background technology]

[0002] For example, Patent Document 1 describes a technique for coating the inside of a chamber that processes plasma. It has been disclosed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-208034 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides techniques for increasing corrosion resistance to process gases. [Means for solving the problem]

[0005] In one exemplary embodiment of the present disclosure, there is provided a showerhead for plasma processing, comprising: A main body portion having a first surface, a second surface opposite to the first surface, and a plurality of inner surfaces. The plurality of inner surfaces extend through the main body from the first surface to the second surface. a body defining a plurality of gas holes, the second surface being constructed from a first corrosion-resistant material; A shower head is provided. [Effects of the Invention]

[0006] According to one exemplary embodiment of the present disclosure, a technique for increasing corrosion resistance to process gases is provided. It can be provided. [Brief explanation of the drawings]

[0007] [Figure 1A] FIG. 2 is a plan view of the shower head SH. [Figure 1B] 1B is a cross-sectional view taken along the line AA in FIG. 1A. [Figure 2A] FIG. 10 is a conceptual diagram for explaining the corrosion resistance effect when a polyimide film is formed as the film CR. [Figure 2B] FIG. 10 is a conceptual diagram for explaining the corrosion resistance effect when the body BD is made of silicon carbide. [Figure 3] 1 is a diagram schematically illustrating a substrate processing apparatus 1. FIG. [Figure 4] 2 is a diagram showing an example of a cross-sectional structure of a substrate W. FIG. [Figure 5] 1 is a flowchart showing an example of a substrate processing method in the substrate processing apparatus 1. [Figure 6] FIG. 4 is a diagram for explaining the flow of a processing gas in the upper electrode. [Figure 7A] FIG. 2 is a perspective view of a gas supply unit GU. [Figure 7B] FIG. 2 is a plan view of the gas supply unit GU. [Figure 7C] FIG. 6C is a cross-sectional view of the gas supply unit GU taken along line AA' in FIG. 6B. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, each embodiment of the present disclosure will be described.

[0009] In one exemplary embodiment, a showerhead for plasma processing includes a first surface a main body portion having a second surface opposite to the first surface and a plurality of inner surfaces, The side surface defines a plurality of gas holes penetrating the body portion from the first surface to the second surface. a second surface made of a first corrosion-resistant material; do.

[0010] In one exemplary embodiment, the first corrosion-resistant material is thicker than the material comprising the body portion. a small amount selected from the group consisting of F2, XeF2, WF6, MoF6, IF7, HF and ClF3 It is a material that has high corrosion resistance to at least one fluorine-containing gas.

[0011] In one exemplary embodiment, the first corrosion-resistant material is thicker than the material comprising the body portion. This material has high corrosion resistance against hydrogen fluoride gas.

[0012] In one exemplary embodiment, the second surface has a film made of a first corrosion-resistant material. .

[0013] In one exemplary embodiment, the inner surfaces further include a membrane.

[0014] In one exemplary embodiment, no membrane is formed on the first surface.

[0015] In one exemplary embodiment, the body is constructed from a first corrosion-resistant material.

[0016] In one exemplary embodiment, the first corrosion-resistant material is a carbon-containing material or a metal-containing material. It is a fee.

[0017] In one exemplary embodiment, the first corrosion-resistant material is a fluorocarbon resin, carbon, Fluorine-doped carbon, polyimide resin, and silicon carbide are selected from the group consisting of Contains at least one species.

[0018] In one exemplary embodiment, the first corrosion-resistant material is a metal, a metal nitride, a metal carbide, or a combination thereof. The material contains at least one selected from the group consisting of a metal, a metal oxide, and an alloy.

[0019] In one exemplary embodiment, the body is constructed from a silicon-containing material.

[0020] In one exemplary embodiment, the silicon-containing material is an electrically conductive silicon-containing material. do.

[0021] In one exemplary embodiment, the silicon-containing material is silicon oxide.

[0022] In one exemplary embodiment, the main body includes a substrate including carbon and a layer covering the surface of the substrate. It is composed of a silicon carbide film.

[0023] In one exemplary embodiment, the body portion is generally disk-shaped, with the first surface being one side of the disk. The first surface constitutes the other surface of the disk, and the second surface constitutes the other surface of the disk.

[0024] In one exemplary embodiment, a shower head and a second surface of the shower head are provided. a gas supply passage for supplying a process gas to the plurality of gas holes of the shower head; and a conductive support.

[0025] In one exemplary embodiment, a third surface of the support facing the second surface of the showerhead The surface is constructed of a second corrosion-resistant material.

[0026] In one exemplary embodiment, the second corrosion resistant material is a semi-sealed anodized coating. It is a membrane.

[0027] In one exemplary embodiment, a gas supply unit for plasma processing comprises an annular a main body portion; a plurality of gas holes provided along a circumferential direction on a radially inner side of the main body portion; a gas supply passage provided inside the gas supply passage and communicating with the plurality of gas holes, A gas supply unit is provided, both of which have an inner circumferential surface made of a first corrosion-resistant material.

[0028] In one exemplary embodiment, a chamber for plasma processing and a plasma processing device provided in the chamber a substrate support and a shower head mounted on the chamber such that the first surface of the shower head faces the substrate support. a substrate processing apparatus including an electrode unit disposed in a plasma generating section, a plasma generating section, and a control section; Provided.

[0029] In one exemplary embodiment, a chamber for plasma processing and a plasma processing device provided in the chamber a substrate support, a gas supply unit attached along the inner wall of the chamber, and a plasma A substrate processing apparatus is provided that includes a generating unit and a control unit.

[0030] In one exemplary embodiment, in a substrate processing apparatus, a chamber is provided for supplying hydrogen fluoride gas. The control unit is connected to a gas source group for supplying a process gas containing controlling the temperature of a third surface of the showerhead opposite the second surface to 220°C or less; placing a substrate having a silicon-containing film on a substrate support; A process for supplying a processing gas into a chamber, and a process for generating plasma from the processing gas by a plasma generating unit. and etching the silicon-containing film. It has been completed.

[0031] In one exemplary embodiment, a substrate processing apparatus includes a gas source group and a gas supply group. a gas supply pipe for supplying a processing gas to the plate processing apparatus, the gas supply pipe including at least A substrate processing system is provided in which the inner circumferential surface is constructed of a third corrosion-resistant material.

[0032] Hereinafter, each embodiment of the present disclosure will be described in detail with reference to the drawings. In the drawings, the same or similar elements are designated by the same reference numerals, and redundant explanations will be omitted unless otherwise specified. Unless otherwise specified, the positional relationships such as up, down, left, and right will be explained based on the positional relationships shown in the drawings. The ratios do not represent actual ratios, and actual ratios are not limited to those shown. There is no.

[0033] <Composition of shower head SH> FIG. 1A is a plan view of a showerhead SH according to one example embodiment. 1B is a cross-sectional view of the showerhead SH of FIG. 1A taken along the line AA. The shower head SH is a shower head for processing. For example, the shower head SH is used to generate plasma. The chamber is configured as follows (hereinafter, simply referred to as "chamber"). It can be used as a member for supplying a processing gas for plasma generation to the internal space of the chamber.

[0034] The shower head SH has a substantially disk-shaped body BD. The body BD has one surface of the disk. The first surface BD1 constitutes the other surface of the disk, and the second surface BD2 is opposite to the first surface BD1. The first surface BD1 and the second surface BD2 are connected to each other via a plurality of inner surfaces BD3. The inner surfaces BD3 are surfaces that are continuous with the first surface BD1 and the second surface BD2. A plurality of gas holes (through holes) GH are defined through the body BD across the first surface BD2. The surface BD1 is the surface of the inner space of the chamber when the showerhead SH is attached to the chamber. The second surface BD1 faces the first surface BD2 and may be exposed to the plasma generated in the chamber. When the showerhead SH is attached to the chamber, the The inner surfaces BD3 may be portions that are not exposed to the plasma generated in the chamber. When the showerhead SH is attached to the chamber, all or part of A part of the inner surface BD3, for example, the vicinity of the first surface BD1, may be an unexposed portion. The gas holes GH are attached to the chamber. In some cases, the nozzle may form part of a flow path that supplies process gas to the chamber.

[0035] The body BD may have any shape. For example, the first and second surfaces may be curved rather than flat. For example, the first surface and the second surface may be curved or may have irregularities. It does not have to be circular in plan view, and may be any shape (for example, circle, ellipse, oval, rectangle, etc.). The first surface and the second surface may be identical or similar in shape to each other, or may be different from each other. The plurality of gas holes GH may each have any shape (for example, a circle, an ellipse, an oval, a rectangle, etc.). The gas holes GH can be arranged in any position (equidistantly, densely arranged in a specific area, etc.). The arrangement can be in the form of a spiral from the center, etc.

[0036] The body BD may be made of, for example, a silicon-containing material. For example, conductive materials such as silicon and silicon carbide are often used, while insulating materials such as silicon oxide (e.g., quartz) are often used. The main body BD may be made of a carbon-containing substrate (core material) and a It may be made up of a silicon carbide film covering the surface.

[0037] The second surface BD of the body BD is made of a first corrosion-resistant material. A film CR made of a first corrosion-resistant material is formed on the second surface BD2 of D. The film CR may also be formed on a plurality of inner surfaces BD3. The thickness of the film CR is, for example, 10 nm to 100 μm. The film CR may or may not be formed on the first surface BD1 of the body BD. Good too.

[0038] The first corrosion-resistant material constituting the film CR is resistant to corrosion by the process gas that can flow through the gas hole BH. Such a processing gas is preferably a gas having high resistance to the plasma generated in the chamber. Gases that are highly corrosive (for example, at room temperature and pressure), such as F2, CF4, SF6, NF3, XeF2, WF6, SiF4, TaF5, IF7, HF, ClF3, ClF5, BrF5 , fluorine-containing gases such as AsF5, NF5, PF5, NbF5, BiF5, UF5, etc. Among these, fluorine-containing gases include F2, XeF2, WF6, MoF6, IF7, HF, and and ClF3. In one example, the gas may be at least one selected from the group consisting of F The first corrosion-resistant material constituting the film CR may be hydrogen fluoride (HF) gas. may be more corrosion resistant than the material from which they are made.

[0039] The first corrosion-resistant material may be, for example, a carbon-containing material or a metal-containing material. are, for example, carbon (e.g., amorphous carbon, diamond, diamond light) carbon or graphite), fluorine-doped carbon, fluorocarbon resin (e.g., polytetrafluoroethylene) polyfluoroethylene), polyimide resin, and silicon carbide. The material may be at least one of the above, and in one example, it may be a polyimide resin or silicon carbide. Metal-containing materials include metals (e.g., platinum, gold, or tungsten), metal nitrides (e.g., iron nitride), and the like. ), metal carbides (e.g., tungsten carbide), metal oxides (e.g., chromium oxide, yttrium oxide) It may be a SiO 2 alloy (e.g., thoria or alumina) or an alloy (e.g., Hastelloy).

[0040] The method for forming the film CR is not particularly limited. For example, the second film CR of the main body BD may be formed by a CVD method. The first corrosion-resistant material is formed on the surface BD2 and the base material on the inner surface BD3 side. The film CR may be formed on the base material on the first surface BD1 side of the body BD. Thereafter, the film CR on the first surface BD1 is removed, so that the second surface BD2 and the inner surface of the body BD are The film CR may remain only on the surface BD3. The film CR on the first surface BD may be removed by, for example, After the shower head SH is attached to the chamber, the first plasma is applied to the plasma generated in the chamber. The film CR may be formed by exposing the surface BD of the body BD. For example, if the body BD is made of a silicon-containing material, the silicon may be nitrided or carbonized. It may be formed in a passivated state, i.e., the film CR may be a passive film.

[0041] In one example, in addition to or instead of forming the film CR, the material constituting the body BD may be selected from the above-mentioned In this case, the second surface may be made of a first corrosion-resistant material without forming the film CR. The surface of the body BD, including BD2, is made of the first corrosion-resistant material.

[0042] 2A and 2B are diagrams illustrating the effect of the first corrosion-resistant material. If the second surface BD2 is made of silicon (single crystal silicon), a native oxide film will be formed on the second surface BD2. Therefore, when the second surface BD2 is exposed to a fluorine-containing gas such as hydrogen fluoride, The Si-O bonds that make up the natural oxide film are broken, and corrosion progresses. This shows an example in which a polyimide film is formed as the film CR on the second surface BD2. It has a hydroxyl group structure and strong intermolecular force of imide bonds. Therefore, it is highly resistant to corrosion by fluorine-containing gases. The corrosion resistance is high, and the corrosion of the second surface BD2 can be suppressed. In this example, the second surface BD2 is made of silicon carbide (SiC). The natural oxide film OF is present on the second surface BD2. When exposed to this, the Si-O bonds that make up the native oxide film OF are broken. Since the main body BD contains carbon atoms, the breaking of Si-O bonds is limited. Corrosion of the second surface BD2 can be suppressed.

[0043] <Configuration of substrate processing apparatus 1> 3 is a diagram schematically illustrating a substrate processing apparatus 1 according to an exemplary embodiment. 1B can be attached to the substrate processing apparatus 1. The substrate processing apparatus 1 to be described is an example in which a shower head SH is used as a top plate 34 of an upper electrode 30. is.

[0044] The substrate processing apparatus 1 shown in FIG. 3 includes a chamber 10. The chamber 10 includes an internal The chamber 10 includes a chamber body 12. The chamber body 12 includes: The chamber body 12 has a substantially cylindrical shape. The chamber body 12 is made of, for example, aluminum. A corrosion-resistant film is provided on the inner wall surface of the main body 12. may be formed from a ceramic such as aluminum oxide, yttrium oxide, or the like.

[0045] A passage 12p is formed in the side wall of the chamber body 12. The substrate W passes through the passage 12p. The passage 12p is connected to the gate 12p. The gate valve 12g is opened and closed along the side wall of the chamber body 12. It will be established.

[0046] A support 13 is provided on the bottom of the chamber body 12. The support 13 is made of an insulating material. The support portion 13 has a substantially cylindrical shape. The support portion 13 has an internal space 10s. The support 13 extends upward from the bottom of the chamber body 12. The substrate support 14 is configured to support the substrate W in the internal space 10s. It has been completed.

[0047] The substrate support 14 includes a lower electrode 18 and an electrostatic chuck 20. The electrode plate 16 may further be formed from a conductor such as aluminum. The lower electrode 18 is provided on the electrode plate 16. The lower electrode 18 is made of a conductor such as aluminum and has a substantially disk shape. The lower electrode 18 is electrically connected to the electrode plate 16.

[0048] The electrostatic chuck 20 is provided on the lower electrode 18. The substrate W is supported by the electrostatic chuck 20. The electrostatic chuck 20 has a body and an electrode. The main body of the electrostatic chuck 20 has a substantially disk shape and is made of a dielectric material. The electrode is a shaped electrode provided inside the main body of the electrostatic chuck 20. The electrode of the electrostatic chuck 20 is connected to a DC power supply 20p via a switch 20s. When a voltage is applied from a DC power supply 20p to the electrostatic chuck 20, electrostatic attraction occurs between the electrostatic chuck 20 and the substrate W. The substrate W is attracted to the electrostatic chuck 20 by the electrostatic force. It is held by an electric chuck 20.

[0049] An edge ring 25 is disposed on the substrate support 14. The edge ring 25 is a ring The edge ring 25 is made of silicon, silicon carbide, quartz, or the like. The substrate W is placed on the electrostatic chuck 20 and in an area surrounded by the edge ring 25. It will be located within the region.

[0050] A flow path 18f is provided inside the lower electrode 18. The flow path 18f is connected to the chamber 1. A heat exchange medium (for example, a cooling medium) is supplied from a chiller unit provided outside the The heat exchange medium supplied to the flow path 18f is supplied to the chiller via the pipe 22b. In the substrate processing apparatus 1, the temperature of the substrate W placed on the electrostatic chuck 20 is is adjusted by heat exchange between the heat exchange medium and the lower electrode 18.

[0051] The substrate processing apparatus 1 is provided with a gas supply line 24. The gas supply line 24 A heat transfer gas (e.g., He gas) is supplied from a heat transfer gas supply mechanism to the upper surface of the electrostatic chuck 20 and the substrate. It is supplied to the gap between the back surface of the W.

[0052] The substrate processing apparatus 1 further includes an upper electrode 30. The upper electrode 30 is disposed above the substrate support 14. The upper electrode 30 is supported on the upper part of the chamber body 12 via a member 32. The member 32 is made of an insulating material. 32 closes the upper opening of the chamber body 12 .

[0053] The upper electrode 30 may include a top plate 34 (shower head SH) and a support 36. The shower head 4 (shower head SH) and the support 36 constitute an example of an electrode unit. The lower surface (first surface BD1) of the shower head SH is the surface on the side of the internal space 10s, The upper surface (second surface BD2) of the top plate 34 (shower head SH) defines the internal space 10s. is the surface that does not face the internal space 10s (i.e., is not exposed to plasma). The upper surface (second surface BD2) of the shower head SH is coated with a corrosion-resistant film CR (see Figure 1). The base material of the top plate 34 (shower head SH) is, for example, silicon or silicon carbide. It is made of conductive materials such as silicon or insulating materials such as silicon oxide (e.g., quartz). The top plate 34 (shower head SH) can be attached to the top plate 34 (shower head SH). The gas discharge holes 34a (gas holes GH) are provided so as to penetrate the substrate in the thickness direction. The inner surface (inner surface BD3) of the top plate 34 defining the gas hole GH is coated with a corrosion-resistant film CR (see FIG. 1) is formed.

[0054] The support 36 is attached to the top surface (second surface) of the top plate 34 (shower head SH). The support 36 is disposed so as to face the top plate 34 (shower head SH). The edge is detachably supported by fastening with bolts or clamping with a clamping member, for example. In one example, an electrostatic chuck is provided on the lower surface of the support 36 (the surface facing the top plate 34). The top surface of the top plate 34 may be attracted and held by an electrostatic chuck. An electrode plate made of the material is sandwiched between a pair of dielectric films, and an electrostatic force is generated by applying a voltage to the electrode plate. The support 36 may be made of, for example, anodized aluminum. The support 36 is made of a conductive material such as aluminum or an aluminum alloy. The support 36 is provided with a gas diffusion chamber 36a. The support 36 has a plurality of ribs extending downward from the gas diffusion chamber 36a. The gas holes 36b are connected to the gas discharge holes 34a, respectively. The support 36 is formed with a gas inlet 36c. The gas inlet 36c is connected to the gas diffusion chamber 36a. The gas diffusion chamber 36a, the plurality of gas holes 36b, and the gas supply pipe 38 are connected to the gas diffusion chamber 36a. The gas inlet 36c and the gas inlet 36c constitute an example of a gas supply path.

[0055] The gas supply pipe 38 is connected to a gas source group 40 via a flow rate controller group 41 and a valve group 42. As with the gas supply pipe 38, a flow rate controller group 41, a valve group 42, and The gas source group 40 is provided outside the substrate processing apparatus 1. The gas source group 40 includes a plurality of The plurality of gas sources includes a source of a process gas. The flow rate controller group 41 includes a plurality of flow rate controllers. Each of the plurality of flow rate controllers in the flow rate controller group 41 is a mass flow controller. The valve group 42 is a flow controller of a pressure control type. Each of the gas sources in the gas source group 40 is connected to a corresponding flow controller in the flow rate controller group 41. The gas supply pipe 38 is connected to the gas supply unit 38 via the corresponding opening and closing valves of the valve group 42. The gas supply pipe 38, the flow rate controller group 41, the valve group 42, and the gas source group 40 are The substrate processing system is configured together with the processing apparatus 1 .

[0056] In the substrate processing apparatus 1, a seal is formed along the inner wall surface of the chamber body 12 and the outer periphery of the support portion 13. The shield 46 is detachably provided. The shield 46 prevents reaction by-products from entering the chamber body 12. The shield 46 is made of a base material, for example, aluminum. The corrosion-resistant film is formed on the surface of the substrate. It may be formed from a ceramic such as yttrium oxide.

[0057] A baffle plate 48 is provided between the support 13 and the side wall of the chamber body 12. The baffle plate 48 is made of, for example, aluminum with a corrosion-resistant coating on the surface. It is made by forming an edible film (such as a film of yttrium oxide). A plurality of through holes are formed in the baffle plate 48. An exhaust port 12e is provided at the bottom of the chamber body 12. The exhaust port 12e has: An exhaust device 50 is connected via an exhaust pipe 52. The exhaust device 50 includes a pressure adjusting valve and a valve. Includes vacuum pumps such as servomolecular pumps.

[0058] The substrate processing apparatus 1 includes a high-frequency power supply 62 and a bias power supply 64. 2 is a power source that generates high frequency power HF. High frequency power HF is suitable for generating plasma. The first frequency is, for example, in the range of 27 MHz to 100 MHz. The high frequency power supply 62 is connected to the lower electrode 1 through the matching box 66 and the electrode plate 16. The matching box 66 is connected to the load side (lower electrode 18 side) of the high frequency power supply 62. It has a circuit for matching the impedance to the output impedance of the high frequency power supply 62. The high frequency power supply 62 may be connected to the upper electrode 30 via a matching box 66. The frequency power supply 62 constitutes an example of a plasma generating unit.

[0059] The bias power supply 64 is a power supply that generates an electric bias. The electrical bias is electrically connected to the electrode 18. The electrical bias has a second frequency. The second frequency is, for example, 400 kHz to 13.56 MHz, and the wave number is lower than the first frequency. Hz range. When used with high frequency power HF, the electrical bias is applied to the substrate support 14 to attract ions to the substrate W. In one example, A bias is applied to the bottom electrode 18. When an electrical bias is applied to the bottom electrode 18, the substrate The potential of the substrate W placed on the support 14 fluctuates within a period defined by the second frequency. The electric bias may be applied to a bias electrode provided in the electrostatic chuck 20. good.

[0060] When plasma processing is performed in the substrate processing apparatus 1, gas is supplied to the internal space 10s. In addition, high frequency power HF and / or an electric bias are supplied to the upper A high frequency electric field is generated between the electrode 30 and the lower electrode 18. The generated high frequency electric field Plasma is generated from the gas in space 10s.

[0061] The substrate processing apparatus 1 further includes a power supply 70. The power supply 70 is connected to the upper electrode 30. In one example, the power supply 70 applies a DC voltage or a low frequency voltage to the upper electrode 30 during plasma processing. For example, the power supply 70 may be configured to supply a negative polarity wave power to the upper electrode 30. DC voltage may be supplied, or low frequency power may be supplied periodically. The power may be supplied as a pulsed wave or a continuous wave.

[0062] The substrate processing apparatus 1 may further include a control unit 80. The control unit 80 includes a processor, a memory, and other components. A computer equipped with any memory unit, input device, display device, signal input / output interface, etc. The control unit 80 controls each part of the substrate processing apparatus 1. The control unit 80 receives an input Using the device, an operator inputs commands to manage the substrate processing apparatus 1. Furthermore, the control unit 80 can display the operating status of the substrate processing apparatus 1 on a display device. Furthermore, the control program and recipe data are stored in the memory. The control program is used to execute various processes in the substrate processing apparatus 1. The processor executes the control program and the recipe data. In one exemplary embodiment, the control unit 80 controls each part of the substrate processing apparatus 1 according to the above. A part or all of these may be provided as part of the configuration of an external device of the substrate processing apparatus 1.

[0063] <Example of substrate W> 4 is a diagram showing an example of a cross-sectional structure of the substrate W. The substrate W is processed in the substrate processing apparatus 1. The substrate W is an example of a substrate that may be used. The substrate W may include, for example, an undercoat film UF, an etching target film EF, and a mask. The film MK may be formed by laminating the layers in this order.

[0064] The undercoat film UF is, for example, a silicon wafer, an organic film formed on a silicon wafer, or a dielectric The undercoat film UF may be a polymer film, a metal film, a semiconductor film, etc. The undercoat film UF may be formed by laminating multiple films. .

[0065] The film EF to be etched is, for example, a silicon oxide film, a silicon nitride film, or a silicon oxynitride film. The silicon-containing film may be a polycrystalline silicon-containing film such as a silicon-oxide film (SiON film) or a silicon-arc film. The film to be etched EF may include a silicon film. The film to be etched EF may be configured by stacking a plurality of films. For example, the film EF to be etched may be a silicon oxide film, a polycrystalline silicon film, or a silicon nitride film. The film may be a laminated film in which at least two films selected from the group consisting of The film EF to be etched is made up of silicon oxide films and polycrystalline silicon films alternately stacked. In one example, the film to be etched EF may be a silicon oxide film and a silicon nitride film. may be configured by alternately stacking them.

[0066] The undercoat film UF and / or the film to be etched EF are formed by CVD, spin coating, etc. The undercoat film UF and / or the film to be etched EF may be a flat film, or Alternatively, the film may have irregularities.

[0067] The mask film MK is formed on the etching target film EF. At least one opening OP is defined on the etching film EF. The space above the film EF is surrounded by the side wall S1 of the mask film MK. The film EF to be etched is formed in the area covered by the mask film MK and the area at the bottom of the opening OP. and an exposed area in the

[0068] The opening OP is formed as follows in a plan view of the substrate W (when the substrate W is viewed from top to bottom in FIG. 4). The shape may be, for example, a hole shape, a line shape, or a combination of a hole shape and a line shape. The mask film MK has a plurality of side walls S1. The plurality of openings OP may each have a linear shape and a constant The openings OP may be arranged at intervals to form a line and space pattern. Each of them may have a hole shape to form an array pattern.

[0069] The mask film MK is, for example, an organic film or a metal-containing film. The organic film is, for example, a spin-on Carbon film (SOC), amorphous carbon film, photoresist film, etc. Metal-containing film Examples of the material include tungsten, tungsten carbide, tungsten silicide, and titanium nitride. The mask film MK may be formed by a CVD method, a spin coating method, or the like. The opening OP may be formed by etching the mask film MK. The mask film MK may be It may be formed by lithography.

[0070] <Example of substrate processing method> FIG. 5 shows an example of a substrate processing method in the substrate processing apparatus 1 (hereinafter referred to as "this processing method"). This processing method involves etching a film EF on a substrate W. In order to achieve this, a processing gas is supplied into a chamber in which the substrate W is placed to generate plasma. This processing method includes a step of preparing a substrate (step ST1) and a step of supplying a processing gas. The method includes a step of generating a plasma (step ST2) and a step of generating a plasma (step ST3). Below, a control unit 80 shown in FIG. 3 controls each unit of the substrate processing apparatus 1 to process the substrate W shown in FIG. The case where this processing method is executed for the above-mentioned object will be explained using an example in the drawings.

[0071] (Step ST1: Preparing the substrate) In step ST1, a substrate W is prepared in the internal space 10s of the chamber 10. In the space 10s, the substrate W is placed on the upper surface of the substrate support 14, and the electrostatic chuck 20 At least part of the process of forming each component of the substrate W is carried out in the internal space 1. 0s. In addition, all or part of the components of the substrate W may be installed outside the substrate processing apparatus 1. After being formed in the apparatus or chamber, the substrate W is loaded into the internal space 10s and supported by the substrate support 1 4 may be placed on the top surface of the

[0072] (Step ST2: Supply of processing gas) In step ST2, a processing gas is supplied from the gas supply unit into the internal space 10s. The chemical gas may include a fluorine-containing gas. The fluorine-containing gas may be F2, CF4, SF6, NF3 , XeF2, WF6, SiF4, TaF5, IF7, HF, ClF3, ClF5, BrF5, As It may be a gas such as F5, NF5, PF5, NbF5, BiF5, UF5, etc., F2, XeF2, The gas may be WF6, MoF6, IF7, HF, ClF3, etc. Also, a fluorine-containing gas is a gas capable of generating hydrogen fluoride (HF) species within chamber 10 during plasma processing. The HF species may include at least one of hydrogen fluoride gas, radicals, and ions. In one example, the fluorine-containing gas may be HF gas or a hydrofluorocarbon gas. The fluorine-containing gas may also be a mixed gas containing a hydrogen source and a fluorine source. The source can be, for example, H2, NH3, H2O, H2O2 or hydrocarbons (CH4, C3H6, etc.). The fluorine source may be NF3, SF6, WF6, XeF2, a fluorocarbon or a hydride. Hereinafter, these fluorine-containing gases will also be referred to as "HF-based gases." The plasma generated from the process gas containing HF gas is called HF species (etchant). The HF-based gas may be the main etchant gas. The HF-based gas is used to remove the reactive oxygen species in the processing gas. The flow rate ratio of the total flow rate of the reaction gas may be the largest. For example, 50% by volume or more, 60% by volume or more, 70% by volume or more, 80% by volume or more, 90% by volume or more The HF-based gas may be 96% by volume or less of the total flow rate of the reaction gas. In some embodiments, the reactive gas does not include a noble gas such as Ar. In addition to the reactive gas, a noble gas may be included.

[0073] The pressure of the processing gas supplied into the internal space 10s is controlled by an exhaust gas pressure regulator connected to the chamber body 12. The pressure of the processing gas is adjusted by controlling the pressure adjusting valve of the device 50. orr (0.7 Pa) or more and 100 mTorr (13.3 Pa) or less, 10 mTorr (1 0.3Pa) or more and 60mTorr (8.0Pa) or less, or 20mTorr (2.7Pa) The pressure should be 40mTorr (5.3Pa) or less.

[0074] (Step ST3: Plasma generation) Next, in step ST3, the plasma generating unit (high frequency power supply 62 and / or bias A power supply 64 supplies high frequency power and / or an electric bias to the upper electrode 3. A high frequency electric field is generated between the substrate support 14 and the processing gas in the internal space 10s. The active species such as ions and radicals in the generated plasma are transferred to the substrate W. The film EF on the substrate W is attracted to the electron beam, and the film EF is etched.

[0075] During plasma generation, the temperature of the lower surface (third surface) 361 (see FIG. 6) of the support 36 is The temperature may be controlled to 220°C or less, 200°C or less, or 180°C or less. The temperature of the lower surface of the support 36 may be controlled to 160° C. or less. Corrosion of the lower surface (third surface) 361 of the support 36 can be more effectively suppressed. The temperature of the third surface 361 is controlled by, for example, passing a heat exchange medium (e.g., a cooling medium) through a flow path provided in the support 36. This can be controlled by supplying a solvent.

[0076] <Processing gas flow at the upper electrode> 6 is a diagram illustrating the flow of the processing gas in the upper electrode 30. Step S At T2, gas is introduced from the gas source group 40 and the gas supply pipe 38 through the upper electrode 30 into the internal space. The processing gas is supplied within 10 seconds. The gas supply path (gas inlet 36c, gas diffusion chamber 36a, and multiple gas holes 36b) The processing gas flows toward the gas discharge holes 34a (gas holes GH) of the power head SH (FIG. 6 arrow A1).

[0077] As shown in FIG. 6, a gap GP is formed between the support 36 and the top plate 34 (shower head SH). In this case, the gas may flow from the gas hole 36b of the support 36 to the top plate 34 (shower head). A part of the processing gas flowing toward the gas discharge holes 34a (gas holes GH) of the nozzle head SH is It can flow towards the gap GP (arrows B1 and B2 in FIG. 6).

[0078] That is, as shown in FIG. 6, the processing gas flows through the gas outlet of the top plate 34 (shower head SH). The inside of the outlet hole 34a (gas hole GH) and the upper surface (second surface BD) of the top plate 34 (shower head SH) 2) The upper surface (second surface BD2) of the top plate 34 is covered with a film CR. Therefore, the processing gas is a corrosive gas (for example, Even if the gas contains a gas containing HF, which has high reactivity even before it is turned into plasma, This can suppress corrosion of the upper surface of the plate 34. As shown in FIG. 6, the gas discharge holes 34a (gas holes GH) If a film CR is also formed on the side surface (inner side surface BD3) that defines the This can prevent the conduction of the upper electrode 30 due to corrosion of the top plate 34 (shower head SH). This can suppress electrical defects and particle generation (contamination of the internal space 10s).

[0079] On the other hand, the underside (first surface BD1) of the top plate 34 (shower head SH) is made of a first corrosion-resistant The lower surface (first surface BD1) does not need to be formed with a film made of a material. 10s and is exposed to the plasma generated in the internal space 10s. Even if the lower surface (first surface BD1) is corroded by the processing gas, the corroded portion is For example, they can be removed relatively easily by exposing them to plasma when cleaning the chamber 10 . On the other hand, the upper surface (second surface BD2) of the top plate 34 is exposed to the plasma generated in the chamber. Since it is not a directly exposed surface, such removal measures are not possible, and the area that can be corroded is large. Therefore, the upper surface of the top plate 34 (first The second surface BD2) is made of a first corrosion-resistant material, and it is effective to suppress the corrosion of the surface itself. In addition, one of the side surfaces (inner side surface BD3) that defines the gas discharge holes 34a (gas holes GH) Although the part (near the internal space 10s) may be exposed to plasma, the entire side surface Therefore, the above-mentioned removal means cannot be used, and therefore the side surface is made of a first corrosion-resistant material, and corrosion itself is prevented. It is effective to suppress the corrosion. In addition, when the main body BD itself is made of the first corrosion-resistant material, In this case, the main body BD is made of a substrate containing carbon and a silicon carbide film covering the surface of the substrate. In this case, the first surface BD1 and the inner surface BD3 are made of the first corrosion-resistant material. It will be composed of:

[0080] Each embodiment of the present disclosure may be modified in various ways without departing from the scope and spirit of the present disclosure. For example, the lower surface (third surface) 361 (the surface defining the gap GP) of the support 36 shown in FIG. ) and the inner circumferential surface of the gas supply path (gas inlet 36c, gas diffusion chamber 36a, and multiple gas holes 36b). 6 and the inner circumferential surface of the gas supply pipe 38 shown in FIG. 6 are both susceptible to corrosion by the processing gas. On the other hand, the part exposed to the plasma generated in the chamber is not the part corroded by the plasma. Therefore, at least a part of these surfaces or the inner circumferential surface is made corrosion-resistant. The structure may be made of a corrosion-resistant material to suppress corrosion itself. In this case, the corrosion-resistant material is For example, the lower surface ( A film of a second corrosion-resistant material may be formed on the third surface 361, and the support 36 itself may be formed of a second corrosion-resistant material. The second corrosion-resistant material may be a semi-sealed anodized In one example, the anodized coating is formed on the lower surface (first surface) of the aluminum support 36. Aluminum oxide formed by anodizing the surface 361 and then semi-sealing the surface 361 The conditions for the semi-porous treatment are not particularly limited, and may be water vapor or boiling water. It may be a chemical sealing treatment using an organic or inorganic substance, or may be an electrolytic treatment using an organic or inorganic substance. The semi-sealing treatment may be an electrochemical sealing treatment performed after anodizing treatment. This is a process to partially seal the pores (voids) that occur on the surface. Even if the object expands, an escape route for the expanded oxide can be secured. Even if the support 36 expands due to heat input from the The pores on the lower surface (third surface) 361 of the support 36 after the semi-sealing treatment can be suppressed. The porosity may be 5% or more, 10% or more, or 15% or more. If the porosity is less than 10%, the support 36 may be cracked due to the heat input from the plasma during the plasma treatment. In addition, holes in the lower surface (third surface) 361 of the support 36 may easily occur. The rate may be 50% or less, 40% or less, or 30% or less. If the porosity exceeds 50%, the physical strength of the lower surface (third surface) 361 of the support 36 decreases. The porosity may be determined by observing the cross section of the support 36 using a scanning electron microscope. Then, by dividing the opening area of ​​the holes by the surface area of ​​the lower surface (third surface) 361 of the support 36, It can be requested.

[0081] Further, for example, a third corrosion-resistant material may be applied to the inner peripheral surface of the gas supply path of the support 36 and / or the gas supply pipe 38. A film of edible material may be formed, and the gas supply passages and / or gas supply tubes 38 of the support 36 may be The first electrode itself may be made of a third corrosion-resistant material. In this case, the third corrosion-resistant material may be a material other than the first electrode. The corrosion-resistant material may be the same as or different from the second corrosion-resistant material.

[0082] Furthermore, for example, the substrate processing apparatus 1 may include a gas supply unit (described below) in addition to the shower head SH. The gas supply unit GU may be the capacitively coupled type substrate processing unit described above. In addition to the device 1, any plasma source such as inductively coupled plasma or microwave plasma may be used. The present invention is applicable to other substrate processing apparatuses.

[0083] FIG. 7A is a perspective view showing a gas supply unit GU according to one example embodiment. 7B is a plan view of the gas supply unit GU. 1 is a cross-sectional view of the gas supply unit GU taken along line A-A' of the gas supply unit GU. The gas supply unit GU is an example of a gas supply means. A plurality of gas supply units GU may be provided in the chamber.

[0084] As shown in FIGS. 7A and 7B, the gas supply unit GU has an annular main body 100. The main body 100 may be made of, for example, a silicon-containing material. The material may be a conductive material such as silicon or silicon carbide, or a silicon oxide (e.g., quartz). The main body 100 has a radially inner side surface 100A and a semi-conductor. The side surface 100B is attached to the inner wall of the chamber. The side surface 100A faces the processing space in the chamber.

[0085] As shown in FIG. 7C, the main body 100 is a hollow body, and the inside of the main body 100 is The gas supply path 102 is provided so as to make a full circle. The gas supply path 102 has a small diameter gas hole. The gas hole 104 is formed on the radially inner side surface 100A of the main body 100. The gas holes 104 are arranged at predetermined intervals along the circumferential direction of the main body 100. There are several provided.

[0086] The gas supply path 102 has at least one gas inlet (not shown). The inlet is an inlet through which processing gases are introduced into the chamber from an external gas source group via gas supply pipes. The process gas flowing into the gas supply path 102 through the gas inlet is 7C. In this example, the lower portion of the side surface 100A where the gas hole 104 is provided is inclined, so that the gas hole The processing gas discharged from 104 is discharged obliquely downward.

[0087] The inner circumferential surface 100C of the main body 100 is made of a first corrosion-resistant material. As shown in the figure, the inner circumferential surface 100C of the main body 100 is covered with the film C made of the first corrosion-resistant material. In one example, instead of or in addition to forming the film CR, the main body 100 The inner circumferential surface 100C of the main body 100 may be made of the first corrosion-resistant material. While the parts exposed to the plasma generated in the chamber may be corroded by Therefore, the inner circumferential surface 1 of the main body 100 is difficult to remove corrosion by plasma. It is effective to make the OOC from the first corrosion-resistant material to suppress corrosion itself. The gas holes 104 may be constructed from a first corrosion-resistant material.

[0088] Embodiments of the present disclosure further include the following aspects.

[0089] (Appendix 1) A showerhead for plasma processing, comprising: a main body having a first surface, a second surface opposite the first surface, and a plurality of inner surfaces; Thus, the plurality of inner surfaces are formed by passing through the main body from the first surface to the second surface. a body defining a plurality of gas holes; the second surface is constructed of a first corrosion-resistant material; Shower head.

[0090] (Appendix 2) The first corrosion-resistant material is more resistant to F2, XeF2, WF6 than the material constituting the main body. fluorine containing at least one selected from the group consisting of MoF6, IF7, HF, and ClF3 2. The showerhead of claim 1, wherein the material is highly resistant to corrosion by oxygen-containing gases.

[0091] (Appendix 3) The first corrosion-resistant material is more resistant to hydrogen fluoride gas than the material constituting the main body. 2. The showerhead of claim 1, wherein the material is highly corrosion resistant.

[0092] (Appendix 4) Any one of Supplementary Note 1 to Supplementary Note 3, wherein the second surface has a film made of the first corrosion-resistant material. The shower head according to any one of claims 1 to 10.

[0093] (Appendix 5) 5. The showerhead of claim 4, further comprising the membrane on the inner surfaces.

[0094] (Appendix 6) 6. The showerhead of claim 4, wherein the film is not formed on the first surface. .

[0095] (Appendix 7) 2. The shower head of claim 1, wherein the body is made of the first corrosion-resistant material. dd.

[0096] (Appendix 8) Item 1 to Item 7, wherein the first corrosion-resistant material is a carbon-containing material or a metal-containing material. 10. The shower head according to claim 1,

[0097] (Appendix 9) The first corrosion-resistant material may be a fluorocarbon resin, carbon, fluorine-doped carbon, polyimide, or the like. at least one selected from the group consisting of silicon carbide and silicon dioxide; 9. The shower head according to claim 8.

[0098] (Appendix 10) The first corrosion-resistant material may be selected from the group consisting of metals, metal nitrides, metal carbides, metal oxides, and alloys. 9. The showerhead according to claim 8, comprising at least one selected from the group consisting of:

[0099] (Appendix 11) 11. Any one of claims 1 to 10, wherein the body is made of a silicon-containing material. Item 1. The shower head described in item 1.

[0100] (Appendix 12) 12. The shower head of claim 11, wherein the silicon-containing material is a conductive silicon-containing material. -head.

[0101] (Appendix 13) 12. The showerhead of claim 11, wherein the silicon-containing material is silicon oxide.

[0102] (Appendix 14) The main body includes a substrate containing carbon and a silicon carbide film covering the surface of the substrate. 12. The showerhead of claim 11, comprising:

[0103] (Appendix 15) The main body is generally disk-shaped, the first surface being one side of the disk, and the second surface being 15. The shower head according to claim 1, wherein the surface of the shower head constitutes the other surface of the disk. -head.

[0104] (Appendix 16) The showerhead according to any one of Supplementary Note 1 to Supplementary Note 15, The shower head is provided on the second surface side thereof, and the plurality of gases of the shower head are and a conductive support having a gas supply path for supplying a processing gas to the hole. knit.

[0105] (Appendix 17) A third surface of the support facing the second surface of the showerhead is a second corrosion-resistant 17. The electrode unit of claim 16, wherein the electrode unit is made of a conductive material.

[0106] (Appendix 18) 18. The method according to claim 17, wherein the second corrosion-resistant material is a semi-sealed anodized coating. Electrode unit.

[0107] (Appendix 19) A gas supply unit for plasma processing, comprising: a ring-shaped main body portion; and a plurality of gas holes provided along a circumferential direction on a radially inner side of the main body portion. and a gas supply passage provided inside the main body and communicating with the plurality of gas holes, At least an inner circumferential surface of the gas supply path is made of a first corrosion-resistant material. Gas supply unit.

[0108] (Appendix 20) a chamber for plasma processing; a substrate support disposed within the chamber; The chamber is provided with a shower head so that the first surface of the shower head faces the substrate support. an electrode unit according to claim 16 or 17 arranged on the upper side; a plasma generating unit; A control unit; A substrate processing apparatus comprising:

[0109] (Appendix 21) a chamber for plasma processing; a substrate support disposed within the chamber; a gas supply unit according to claim 19 attached along an inner wall of the chamber; a plasma generating unit; A control unit; A substrate processing apparatus comprising:

[0110] (Appendix 22) The chamber is connected to a group of gas sources for supplying process gases including hydrogen fluoride gas. And, The control unit The temperature of the third surface of the support, which faces the second surface of the showerhead, is set to 200 a step of controlling the temperature to 0.5 ° C. or less; placing a substrate having a silicon-containing film on the substrate support; supplying the process gas from the gas sources into the chamber; The plasma generating unit generates plasma from the processing gas, and Etching the film; 22. The substrate processing apparatus of claim 20, configured to perform a process including:

[0111] (Appendix 23) The substrate processing apparatus value according to Appendix 20 or Appendix 21; a group of gas sources; a gas supply pipe for supplying processing gas from the gas source group to the substrate processing apparatus; Including, At least an inner circumferential surface of the gas supply pipe is made of a third corrosion-resistant material. Substrate processing system.

[0112] (Appendix 24) A support for supporting a shower head of a plasma processing apparatus, the support has a gas supply path for supplying a process gas to the showerhead; The support surface that supports the showerhead is made of a second corrosion-resistant material. support.

[0113] (Appendix 25) 25. The method according to claim 24, wherein the second corrosion-resistant material is a semi-sealed anodized coating. support. [Explanation of symbols]

[0114] 1...substrate processing apparatus, 10...chamber, 10s...internal space, 12...chamber body, 14...substrate support, 16...electrode plate, 18...lower electrode, 20...electrostatic chuck , 30... upper electrode, 34... top plate, 34a... gas discharge hole, 36... support, 38... Gas supply pipe, 50...exhaust device, 62...high frequency power supply, 64...bias power supply, 80... Control section, CT...control section, EF...film to be etched, MK...mask film, OP...opening, UF: Undercoat, W: Substrate, SH: Top plate, CR: Corrosion-resistant film, BD: Main body, BD1...first surface, BD2...second surface, BD3...inner surface, GH...gas hole, GH... …gas supply unit

Claims

1. 1. A showerhead assembly for use in a plasma processing apparatus, comprising: a showerhead formed of a silicon-containing material having a first surface and a second surface opposite the first surface, the showerhead having a plurality of first gas holes extending from the second surface to the first surface; a conductive support having a third surface opposite the second surface of the showerhead and a plurality of second gas holes extending to the third surface, the plurality of second gas holes respectively communicating with the plurality of first gas holes, and a gap being formed between the second surface and the third surface, the conductive support including a conductive support having a coolant flow path; a first corrosion-resistant film formed on the third surface; The coolant supplied to the coolant flow path is controlled so that the temperature of the third surface is 200 degrees or less.

2. 10. The showerhead assembly of claim 1, wherein the first corrosion-resistant film is a semi-sealed anodized film.

3. 3. The showerhead assembly of claim 2, wherein the anodized coating is an aluminum oxide film.

4. 3. The showerhead assembly of claim 2, wherein the anodized coating comprises pores.

5. 5. The showerhead assembly of claim 4, wherein the porosity of the anodized coating is 5% or more.

6. 5. The showerhead assembly of claim 4, wherein the porosity of the anodized coating is 50% or less.

7. 10. The showerhead assembly of claim 1, wherein the conductive support is composed of aluminum or an aluminum alloy.

8. 10. The showerhead assembly of claim 1, wherein the conductive support includes a gas diffusion chamber in communication with the plurality of second gas holes.

9. 9. The showerhead assembly of claim 8, further comprising a second corrosion-resistant film formed on at least a portion of inner circumferential surfaces of the gas diffusion chamber and the plurality of second gas holes.

10. 10. The showerhead assembly of claim 9, wherein the second corrosion-resistant film is formed of the same material as the first corrosion-resistant film.

11. 10. The showerhead assembly of claim 9, wherein the second corrosion-resistant film is formed of a different material than the first corrosion-resistant film.

12. The showerhead assembly of any one of claims 9 to 11, further comprising a third corrosion-resistant film formed on the second surface.

13. a chamber; a substrate support disposed within the chamber; the showerhead assembly of claim 11 positioned above the substrate support; a plasma generating unit configured to generate plasma within the chamber; A control unit; A plasma processing apparatus comprising:

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